1. Field of the Invention
This invention relates to a conveyor for raising and lowering articles having numerous physical shapes and sizes such as cans, cartons, cases, etc.
2. Background Information
Many types of conveyors have been previously provided for raising or lowering cans, bottles, etc. from one location to another. Such conveyors are generally called vertical conveyors. When the conveyors are used to elevate articles from one location to a higher location, they are called elevating conveyors. When the vertical conveyors are used to lower articles from one location to a lower location, they are generally referred to as lowerators. For example, a device is described in U.S. Pat. No. 4,756,403 for lowering and lifting containers. In U.S. Pat. No. 4,756,403, the cylindrical containers are held in semi-circular recesses and are raised or lowered in those recesses by means of a spiral guide bar or inclined support means. It is believed that the device of the '403 patent could not be used or modified to handle cartons or cases due to the inclusion of the semi-circular recesses.
U.S. Pat. No. 2,628,708 discloses an article raising or lowering conveyor. As in the '403 patent, the articles in the '708 apparatus are held in recesses, with those recesses being rotated so that the bottles or cans are raised in the recesses by pusher bar assemblies. As with the '403 device, it is believed that the conveyor of the '708 patent may not be used to raise or lower articles having various physical shapes such as cartons, cases, etc.
The conveyor equipment now in use generally employs a conveyor means extending at 5.degree. to 10.degree. of incline. This minimum incline is needed to prevent slip-back of the article. In those elevators which only have a 5.degree. to 10.degree. of incline, the conveyor consumes considerable space and distance to gain elevation thereby consuming valuable floor space. The same is true of a lowerator of the same design. Another prior art method is a magnetic means which is usable only on ferrous containers. A magnetic elevator consumes less floor space but is limited to objects which are attracted to a magnet.
Other types of elevators used for larger objects employ moving platforms which drive through a frame to elevate objects from one level to another. Elevators of this type take less floor space but are limited to a slower operation.